1. Technical Field
The present invention relates to an electrophoresis particle, a method of manufacturing electrophoresis particle, an electrophoresis dispersion liquid, an electrophoresis sheet, an electrophoresis device and an electronic apparatus.
2. Related Art
Generally, when an electric field is applied to a dispersion system in which tiny particles have been dispersed in a liquid, it is known that tiny particles are moved (migrated) in a liquid by Coulomb's force. This phenomenon is called electrophoresis, and in recent years, an electrophoresis display device which displays the desired information (image) using this electrophoresis has attracted attention as a new display device.
This electrophoresis display device is provided having a display memory property and a wide viewing angle property of the status in which a voltage impression is stopped, and being able to display a high contrast with low power consumption, or the like.
In addition, the electrophoresis display device is also better for eyes when compared to a radiative type display device such as a cathode-ray tube due to it being a non-radiative type device.
It is known that such an electrophoresis display device is provided with an electrophoresis dispersion liquid in which the electrophoresis particles are dispersed in a solvent as an electrophoresis dispersion liquid arranged between a pair of substrates which have an electrode.
In the electrophoresis dispersion liquid of the above configuration, electrophoresis particles including positive charging particles and negative charging particles are used as an electrophoresis particle, and in this manner, it becomes possible to display the desired information (image) by a voltage being applied between a pair of substrates (electrodes).
Here, the electrophoresis particles, including a covering layer in which polymer molecules are linked with respect to the substrate particles generally, are used as an electrophoresis particle, and it becomes possible to disperse and charge the electrophoresis particles in the electrophoresis dispersion liquid by setting a configuration provided such a covering layer (the polymer molecule).
In addition, the electrophoresis particles of the above configuration, for example, are manufactured using atom transfer radical polymerization (ATPR) as follows.
That is, the substrate particles are prepared, and after a silane coupling agent having a polymerization initiating group being bonded onto the surface of the substrate particles, the electrophoresis particles are manufactured by being provided polymer molecules (polymers) in which a monomer has been polymerized using living radical polymerization, setting the polymerization initiating group as the starting point (for example, JP-A-2007-225732).
However, in a case of manufacturing the electrophoresis particles using such an ATPR, since the electrophoresis particles are formed on the surface of the substrate particles by the polymer molecules being directly linked, the charge of the electrophoresis particles (charged status) depends on the charge of the substrate particles as well as the linked polymer molecules. Therefore, in order to impart the aimed for dispersibility and the electrification property to the electrophoresis particles, there is a need to set the number of the polymer molecules which are linked and the electrification amount individually according to the type of the substrate particles, so there are problems in that time and trouble are required.
Therefore, the development for the method of manufacturing the electrophoresis particles which is able to impart the aimed for dispersibility and the electrification property to the electrophoresis particles without depending on the charge of the substrate particles, in other words, without, associating with types of the substrate particles is demanded.